Energy consumptions of HVAC systems for buildings are significant portions of overall energy consumptions. Therefore, energy management systems for HVAC systems that could significantly reduce energy consumption will be very useful. However, most of the energy management systems are basically monitoring systems, rely heavily on human interventions for actual management and controls. There are few optimized energy control systems based on automatic control sequence to specifically control system operating conditions.
For example, U.S. Pat. No. 9,026,261, “Methods and systems for managing energy usage in buildings” mostly disclosed energy usage monitoring and data recording systems. U.S. Pat. No. 8,235,776, “Fully articulated and comprehensive air and fluid distribution, metering, and control method and apparatus for primary movers, heat exchangers, and terminal flow devices” and U.S. Pat. No. 7,216,698, “Air-conditioning system” failed to provide comprehensive automatic control logic to achieve automatic control. U.S. Pat. No. 7,216,021, “Method, system and computer program for managing energy consumption” mostly provide operation data analysis but failed to provide actual workable operation logic for daily operations.